Synthesis and Coordination Behaviour of a Novel Tridentate P,N,O‐Ketiminate Ligand

Treatment of o ‐(diphenylphosphino)aniline with 3‐formylacetylacetone led to the formation of the ketimine type Schiff base 3‐(( o ‐diphenylphosphino‐phenylamino)‐methylene)‐pentane‐2,4‐dione ( o −PPh 2 −C 6 H 4 −NH−CH=C(COCH 3 ) 2 , HL). Complexes [ML 2 ] (M=Fe, Co, Ni, Cu) were obtained from the reaction of HL with the corresponding metal acetate or acetylacetonate derivatives. The [ML 2 ] complexes (M=Fe, Co, Ni) exhibit a distorted octahedral coordination from two tridentate P,N,O ketiminate ligands L − . The arrangement of the ligands is meridional in the case of [FeL 2 ] and [NiL 2 ] . The cobalt complex [CoL 2 ] displays a facial coordination. In the case of the nearly square planar copper complex [CuL 2 ], only the ketiminate functionalities of the ligands are involved in coordination and the participation of the PPh 2 groups is neglectable.